S and P waves from an earthquake travel at different speeds, and this difference

S and P waves from an earthquake travel at different speeds, and this difference helps in the determination of the earthquake "epicenter" (where the disturbance took place).

(a) Assuming typical speeds of 8.6 km/s and 5.8 km/s for P and S waves, respectively, how far away did the earthquake occur if a particular seismic station detects the arrival of these two types of waves 1.0 min apart? km(b) Is one seismic station sufficient to determine the position of the epicenter?